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941.
The focus of the present study was on determining whether the high level of directional accuracy found in aiming studies in which the subjects can see their hand in the visual periphery supports the existence of a kinetic visual channel or, rather, the advantage of binocular over monocular vision for movement directional control. The limits of this kinetic visual channel were also explored. The results of the 1st experiment indicated that seeing one's hand in the visual periphery is sufficient to ensure optimal directional aiming accuracy. Further, no differences in aiming accuracy were noted between monocular and binocular vision. These results supported the existence of a visual kinetic channel. In the 2nd experiment, whether this kinetic visual channel would operate with movements slower (55 degrees /s) than those usually used in studies that had proved its existence (over 110 degrees /s) was delineated. The results indicated that this visual kinetic channel was operative even at relatively slow movement velocities. Central vision of the hand seemed to be used for on-line directional control of relatively slow movements.  相似文献   
942.
A total of 229 late adolescents (a large majority 15 to 19 years of age) completed a questionnaire that assesses a broad range of videogame-relevant experiences, preferences, and attitudes. Videogame playing was found to be a more popular, and a more highly regarded, activity among males than females. Gender differences were also found in participants' ratings of their motivations for playing videogames, their evaluations of particular characteristics of videogames, and their selection of their “most favorite” videogame. The differences between frequent and infrequent videogame players appeared to be limited to differences in the extent to which videogame playing is pursued and evaluated as a positive leisure activity, rather than reflecting broad differences in interest or personality. Some relations were found between participants' self-reported personality characteristics (i.e., self-esteem, empathy, conscientiousness, and introversion) and their attitudes toward videogames.  相似文献   
943.
Our research focused on the implicit beliefs of potential brainstormers about the possible outcomes of brainstorming. We conducted four studies to assess the relative importance of quality and quantity as goals of brainstorming. In Study 1, we found evidence for a quality over quantity hypothesis: participants indicated that it was more important to produce creative, original, and high quality ideas than to generate a large number of ideas. In Studies 2 and 3, participants displayed support for the quality over quantity hypothesis by showing in group favoritism for a quality dimension but not a quantity dimension. Study 4 showed that participants believed brain-storming would enhance the quality of others' ideas more than one's own ideas, but they did not display a similar bias about idea quantity.  相似文献   
944.
945.
This study investigated the relationship between overt and subtle forms of racism with Whites' recommendations for capital sentencing of Black and White offenders convicted of murder. White participants (n= 104) viewed 5 other “jurors” (all Whites or 4 Whites and 1 Black) on videotape individually presenting their decisions to vote for the death penalty in the case. It was hypothesized that the bias of high prejudice-scoring participants would be overt, but that the pattern for low prejudice-scoring participants would be more complex. As predicted, among high prejudice-scoring participants, Black defendants received stronger recommendations for the death penalty than did White defendants. Among low prejudice-scoring White participants, Black offenders received stronger recommendations for the death penalty only when a Black juror advocated the death penalty.  相似文献   
946.
Previous research has established the existence of homogeneous religious coping profiles in cardiac-transplantation candidates labeled as the deferring/collaborators, self-directors, and the eclectic religious copers. However, their prospective impact on outcome has not yet been established. This paper examines potential differences between pre-cardiac transplantation religious coping cluster groups on post-cardiac transplantation quality of life (physical functioning, mental health, and general health). Results indicated that the religious coping profiles of deferring/collaborators and self-directors had significantly better scores on mental health and general health than did the eclectics. Implications for religious-coping research and clinical practice are discussed.  相似文献   
947.
Schedule interactions involving punishment with pigeons and humans   总被引:1,自引:1,他引:0       下载免费PDF全文
The principal aim of the present experiments was to assess whether punishment increased or decreased the rate of unpunished behavior (contrast and induction, respectively) for which reinforcement rate was held constant, with physical and nonphysical punishers (electric shock and response cost), pigeon and human subjects, signaled and unsignaled components (multiple and mixed schedules), and the presence or absence of a blackout period between components. Across the three experiments there were 20 punishment conditions. Induction was found in nine of those, less consistent response-rate reduction was found in three, contrast was found in four, and in four there was no change in responding from conditions without punishment. Contrast occurred consistently only with multiple schedules during the first exposure to electric-shock punishment. Induction and no change, however, were found with every combination of the independent variables studied. Four conclusions regarding the interactions between punished and unpunished responding emerged from the present results: (a) Both contrast and induction occurred with the reinforcement rate held constant and a blackout between components, (b) induction was more common than contrast, (c) contrast occurred only in the presence of a stimulus different from that correlated with the punisher, and (d) contrast diminished with prolonged exposure to punishment. None of the current theoretical accounts of punishment contrast can explain the present results.  相似文献   
948.
Response-independent Events In The Behavior Stream   总被引:2,自引:2,他引:0       下载免费PDF全文
The metaphor of the behavior stream provides a framework for studying the effects of response-independent food presentations intruded into an environment in which operant responding of pigeons was maintained by variable-interval schedules. In the first two experiments, response rates were reduced when response-independent food was intruded during the variable-interval schedule according to a concomitantly present fixed-time schedule. These reductions were not always an orderly function of the percentage of response-dependent food. Negatively accelerated patterns of key pecking across the fixed-time period occurred in Experiment 1 under the concomitant fixed-time variable-interval schedules. In Experiment 2, positively and negatively accelerated and linear response patterns occurred even though the schedules were similar to those used in Experiment 1. The variable findings in the first two experiments led to three subsequent experiments that were designed to further illuminate the controlling variables of the effects of intruded response-independent events. When the fixed and variable schedules were correlated with distinct operanda by employing a concurrent fixed-interval variable-interval schedule (Experiment 3) or with distinct discriminative stimuli (Experiments 4 and 5), negatively accelerated response patterns were obtained. Even in these latter cases, however, the response patterns were a joint function of the physical separation of the two schedules and the ratio of fixed-time or fixed-interval to variable-interval schedule food presentations. The results of the five experiments are discussed in terms of the contributions of both reinforcement variables and discriminative stimuli in determining the effects of intruding response-independent food into a stream of operant behavior.  相似文献   
949.
In the area of child psychosocial intervention research, substantial progress in addressing challenging methodological issues has been made. In this article we suggest that continued movement forward requires maintaining a balance between methodological and theoretical issues, and that it would be advantageous to begin to think about matching advances in methodological sophistication by similar advances in theoretical sophistication. The need to advance our understanding of theoretical issues is especially important in light of the challenges raised by postmodernism, particularly as these challenges relate to knowledge development. We discuss these challenges and describe how a pragmatic orientation may be a useful way to respond to them. We also describe how a pragmatic orientation has been useful in our work in developing, implementing and evaluating psychosocial interventions for children with phobic and anxiety disorders.  相似文献   
950.
The ability to compensate for fixation of the jaw by a bite block was investigated in 6 nonfluent aphasics, 6 fluent aphasics, and 10 normal control subjects. Acoustic analyses of the vowels [i u a æ] and fricatives [s s] revealed substantial but incomplete compensation for the perturbation in all three subject groups. Perceptual identification scores and quality ratings by naive and phonetically trained listeners indicated poorer identification of the high vowels [i u] under compensatory conditions relative to normal production. Of particular interest was the fact that all three groups of subjects exhibited similar patterns of results. The findings suggest that any deficit in speech motor programming demonstrated by the nonfluent aphasic patients did not affect compensatory abilities. Results are discussed with respect to normal speech adaptation skills and the nature of articulatory breakdown in nonfluent aphasia.  相似文献   
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